Rotary pump, compressor, and the like



Nov.. l2, i935.

ROTARY PUMP; COMPRESSOR AND THE LIKE Filed May l()l .1934

INVENTOR A TTORNE Y Patented. Nev.' 12, 1,935

ROTARY PUW, OMPRESSR, AND THE LME lohn Southern, London,

England, asslgnor .to

, Worthington Pump and Machinery Corpora- L tion, New Yorin, N. ll., a. corporation or Virginia l Application May 10, 19341, Serial No. 724,88@ lin Great Britain .Fully 1, 1933 e anims.. (ci. its-13s) This invention relates to rotaryv displacement i pumps,vcompressors and the like, of the type comprising a rotary `drum carrying sliding vanes, plates or pistons mounted eccentrically within a stationary casing, the vanes reciprocating within guides or Vslots in the drum as the latter revolves. In such pumps, in order to reduce friction losses, the vanes have been guided so that they rotate 'with their tips just clear of the casing wall by the provision of floating rings rotatably located in annular grooves in the casing end walls and with which trunnions on the vanes are engaged.

An object of the present invention is to provide a pump of the type indicated having increased emciency and'in which inparticular frictional losses are still further reduced.

According to the invention oating rings of channel shape in section are provided and driven by the drum or rotor ofthe pump through shoes associated with the vane trunnons either by positive connection of one vane shoe or by resiliently loaded friction means.

The sliding vanes may be provided with end trunnions seated within curved shoes or blocks which are mounted within the channel rings, the blocks associated with one oi the vanes being fastened to the iioating rings.

According to another form one or more (pairs) of the shoes or blocks are divided and the parts frictionally engaged with the sides or the channel rings byresilient means such as springs so'that the blocks while being nrmly engaged with the rings are free enough to accommodate themselves in' working 'or to give or slide under overload or undue strain.

A further feature of the invention lies in the provision or a cavity or arcuate recess in the casing wall but coaxial with the drum .or rotor to anord an extended sealing area between the suction and discharge sides of the pump.

It will be appreciated that the outer ends oi the vanes tend to revolve on a circle the center of which is that of the oating rings but as the vanes are constrained by their radial mounting in thedrum which is' eccentric lto thecasing and floating rings, the vanes do not follow a truly circular path. With thisv condition in View the invention also consists in making the inner-peripheral wall of the casing or pump chamber slightly elliptical in accordance with the displacement of the axes of the drum or rotor and the floating rings. 1

Another feature of the invention comprisgs the provision of vents or ducts leading from the conipartments in the slgts or guides in the rotor' Y pressors and the like of the preferred form,

`which seat d have a sliding rit within cess being eccentric to the drum shaft.

n,as byrivets li. one vane may hind the vanes to the .pump chamber to adorda free passage for entrapped iiuid.

With these and other objects in view as may appear from the accompanying specication, the invention consists of various features, of con- 5 struction and combination of parts, which will berst described in connection with the accompanying drawing, showing rotary pumps. comand the features forming the invention will be spe l0 cifically pointed out in the claims.

In the drawing:

Fig. 1 is a longitudinal section through a pump constructed in accordance with the invention.

Fig. 2`isI an end view partly in section of the l5 pump shown in Fig. l, the left half being a secn tion on the line 2-2 andthe right half being a section on the line 3-3 of Fig. l.

Fig. 3 is a fragmentary section similar to 2 illustrating a modified form of the pump.

In carrying the invention into enect according to one convenient mode by way of example. a rotary drum i is mounted eccentrlcally within a stationary casing or pump chamber t 'having inlet and discharge ports n and t respectively. 26 The drum i is driven by a shaft it coupled to a motor il upon which the casing t maybe carried by the housing it. The drum is provided with a plurality of radially.. arranged sliding vanes i (four in the example illustrated) which are pro 3o y* jected outwardly by centrifugal force Fas the drum rotates.

Each vane is provided with end trunnlons t within curved blocks s. The blocks shaped member or ring l@ (see Fig. l) which is located within a circular recess il in the end wall i2 ofthe stationary pump casing, such re- .a sughi. i clearance is provided between the outer surface 4o oi the ring l@ and the recess il. The trunnions t' on the ends of the vanes opposite' to the trunnions t seatwithin the curved shoes or blocks t which in turn have asliding nt in t e ring in. The ring ld' is carried by the housing it.

The rings lil are adapted .to rotate with the drum i for which purpose the end curved blocks Q of one of the vanes are fastened to the rings It will be appreciatedthat only be connected to to the eccentric mounting vbetween the drum t and the rings which causes the blocks to approach and recede from one anotherin accommodating themselves as the drum rotates.

During the period when a pair of blocks 9 is 55 an annular -channela5 the rings owingA 5o .from the axis of the rotor.

approaching one another the space therebetween (such as I4, Fig. 2) will decrease in volume and in order to prevent breakage in the event of a liquid being present in such space the curved blocks lare grooved, as at I5, Fig. 1, to provide communication between the spaces Il between the blocks.

I'he inner peripheral wall oi' the casing forms an arcuate recess 3a the arc of which is struck an extended area for sliding contact with the rotor so that an effective seal is provided between the suction and delivery sides of the pump, as contrasted with the usual line sealing contact.

For the reason already explained .the inner peripheral wall of the casing is slightly elliptical, the portions in the region of the reference 3b being a slightly atter curve than the rest of the Wall.

In order to liberate any iluid entrapped in the pockets or compartments 'la behind the vanes, vent grooves `or ducts such as Ib may be provided in the rotor against the face of the vanes.

During the operation of the pump, as the drum I.

revolves the ring members I will be carried round by the trunnions 8 associated with the blocks 9 which are xed to the rings. During the part of the revolution when the eccentricity increases the free blocks 9 will have a slightly backward movement relatively to the rings while during the part of the revolution when the eccentricity decreases, these blocks will have a slight forward movement; relatively to the rings.

According to another mode of carrying part of the invention into eiect as 'shown in the modied form of the pump illustrated in Fig. 3, one or more of the vane shoes or blocks 9 may be slipfrictionally coupled to the oating channel rings lll. In one form a shoe (or shoes) may be divided and the two parts 9a and 9b cavitated, see 9c in Fig. 3. In the cavities are seated helical springs 9d which constantly tend to separate the parts 9a and 9b and thrust the outer surfaces against the sides of the channel ring and afford a frictional engagement which is suiiicient. to cause the rings to be driven with the 'rotor but will allow the blocks to accommodate themselves circumferentially or give or slide under any undue strain. The trunnions of the vanes may be located between the divided parts 9a and 9b or they may be located entirely in one part or the other, the part independent of the trunnion operating simply as a thrust block under the resilient pressure of the springs.

'I'he inner wall of the pump casing may be shaped to a Working fit with the drum at the upper part.

In all other respects the pump shown in Fig. 3 is similar to that shown in Figs. 1 and 2.

The pump illustrated is suitable for delivering water or other liquid and operates-effectively without priming.

The improvement according to the invention may also be applied with any necessary modication to rotary vane air compressors.

It will be understood that the invention is not to be limited to the specic construction or ar- 'Ihisrecess affords casing, a rotor in said ,casing, a rotor in said rangement of parts shown, but that these may be modiiied widely within the invention as deilned by the claims.

What is claimed is:

1. In a rotary pump, compressor or the like, a

casing', a rotor in said casing, oating rings of channel shape in cross-section carried by said rotor, vanes slidably carried by said rotor, trunnions on said vanes, shoes in said rings and connected to said trunnions, said shoes being spaced 10 one'from the other and provided with grooves to permit communication between the spaces between the shoes.

2. In a rotary pump, compressor or the like,

a casing, a rotor in said casing, floating rings J5 o! channel shape in cross section carried by said rotor, vanes slidably carried by said rotor, trunnions on said vanes, shoes in said rings and connected to said trunn'ions, means for urging said shoes into frictional driving engagement with said iloating rings, said shoes being spaced one from the other and provided with grooves to permit communication between the spaces between the shoes.

3. ,In a rotary pump, compressor or the like, a

casing, iloating rings of channel shape in cross-section carried by said rotor, vanes slidably carried by said rotor, trunnions on said vanes, shoes in said rings and connected to said trunnions, and resilient means carried by said shoes for urging the shoes into frictional driving engagement with said oating rings.

4. In a. rotary pump, compressor or the like, a casing, a rotor in said casing, oating rings of channel shape in cross-section carried by said rotor, vanes slidably carried by said rotor, trunnions on said vanes, shoes in said rings and connected to said trunnions, and resilient means carried by said shoes for urging the shoes into 10 frictional driving engagement with said floating rings, said vanes being provided with ducts to permit escape of uid from behind the inner ends of the vanes.

5. In a rotary pump, compressor or the like, a

casing, floating rings ot channel shape in cross-section carried by said rotor, vanes slidably carried by said rotor, trunnions on said vanes, shoes in said rings and connected to said trunnions, and resilient means carried by saidshoes for urging the shoes into frictional driving engagement with said floating rings, said shoes being spaced one from the other and provided with grooves to permitcommunication between the spaces between the shoes. 53

6. In a rotary pump, compressor or the like, a casing, a rotor in said casing, oating rings of channel shape in cross-section carried by said rotor, vanes slidably carried by said rotor, trunshoes.

J OHN SOUTHERN. 

